AU2023201986B2 - Analyzer with a positive displacement pump and a valve and analysis process with such an analyzer - Google Patents
Analyzer with a positive displacement pump and a valve and analysis process with such an analyzer Download PDFInfo
- Publication number
- AU2023201986B2 AU2023201986B2 AU2023201986A AU2023201986A AU2023201986B2 AU 2023201986 B2 AU2023201986 B2 AU 2023201986B2 AU 2023201986 A AU2023201986 A AU 2023201986A AU 2023201986 A AU2023201986 A AU 2023201986A AU 2023201986 B2 AU2023201986 B2 AU 2023201986B2
- Authority
- AU
- Australia
- Prior art keywords
- unit
- valve
- measuring chamber
- suction chamber
- input
- Prior art date
- Legal status (The legal status is an assumption and is not a legal conclusion. Google has not performed a legal analysis and makes no representation as to the accuracy of the status listed.)
- Active
Links
- 238000000034 method Methods 0.000 title claims abstract description 31
- 230000008569 process Effects 0.000 title claims abstract description 27
- 238000004458 analytical method Methods 0.000 title description 6
- 238000006073 displacement reaction Methods 0.000 title description 3
- 239000012530 fluid Substances 0.000 claims abstract description 181
- 239000000126 substance Substances 0.000 claims abstract description 39
- 238000012546 transfer Methods 0.000 claims abstract description 27
- 230000001360 synchronised effect Effects 0.000 claims description 9
- 230000001960 triggered effect Effects 0.000 claims description 5
- 230000008878 coupling Effects 0.000 claims description 4
- 238000010168 coupling process Methods 0.000 claims description 4
- 238000005859 coupling reaction Methods 0.000 claims description 4
- LFQSCWFLJHTTHZ-UHFFFAOYSA-N Ethanol Chemical compound CCO LFQSCWFLJHTTHZ-UHFFFAOYSA-N 0.000 abstract description 22
- 238000007789 sealing Methods 0.000 description 49
- 239000003570 air Substances 0.000 description 37
- 206010006326 Breath odour Diseases 0.000 description 29
- 235000019441 ethanol Nutrition 0.000 description 21
- 210000004072 lung Anatomy 0.000 description 18
- 238000005259 measurement Methods 0.000 description 15
- 239000008280 blood Substances 0.000 description 13
- 210000004369 blood Anatomy 0.000 description 13
- 239000003792 electrolyte Substances 0.000 description 12
- 238000006243 chemical reaction Methods 0.000 description 7
- 238000011144 upstream manufacturing Methods 0.000 description 7
- 238000001514 detection method Methods 0.000 description 6
- 230000029058 respiratory gaseous exchange Effects 0.000 description 5
- 230000000694 effects Effects 0.000 description 4
- BASFCYQUMIYNBI-UHFFFAOYSA-N platinum Chemical compound [Pt] BASFCYQUMIYNBI-UHFFFAOYSA-N 0.000 description 4
- 210000002345 respiratory system Anatomy 0.000 description 4
- 230000000903 blocking effect Effects 0.000 description 3
- 238000009530 blood pressure measurement Methods 0.000 description 3
- 238000013461 design Methods 0.000 description 3
- 238000011156 evaluation Methods 0.000 description 3
- 239000000446 fuel Substances 0.000 description 3
- 238000010926 purge Methods 0.000 description 3
- NBIIXXVUZAFLBC-UHFFFAOYSA-N Phosphoric acid Chemical compound OP(O)(O)=O NBIIXXVUZAFLBC-UHFFFAOYSA-N 0.000 description 2
- QAOWNCQODCNURD-UHFFFAOYSA-N Sulfuric acid Chemical compound OS(O)(=O)=O QAOWNCQODCNURD-UHFFFAOYSA-N 0.000 description 2
- 230000008901 benefit Effects 0.000 description 2
- 238000001311 chemical methods and process Methods 0.000 description 2
- 239000003251 chemically resistant material Substances 0.000 description 2
- 238000009792 diffusion process Methods 0.000 description 2
- 230000008020 evaporation Effects 0.000 description 2
- 238000001704 evaporation Methods 0.000 description 2
- 238000011010 flushing procedure Methods 0.000 description 2
- PCHJSUWPFVWCPO-UHFFFAOYSA-N gold Chemical compound [Au] PCHJSUWPFVWCPO-UHFFFAOYSA-N 0.000 description 2
- 239000010931 gold Substances 0.000 description 2
- 229910052737 gold Inorganic materials 0.000 description 2
- 239000012528 membrane Substances 0.000 description 2
- 230000003647 oxidation Effects 0.000 description 2
- 238000007254 oxidation reaction Methods 0.000 description 2
- 239000002245 particle Substances 0.000 description 2
- VLTRZXGMWDSKGL-UHFFFAOYSA-N perchloric acid Chemical compound OCl(=O)(=O)=O VLTRZXGMWDSKGL-UHFFFAOYSA-N 0.000 description 2
- 229910052697 platinum Inorganic materials 0.000 description 2
- 238000005070 sampling Methods 0.000 description 2
- 238000012360 testing method Methods 0.000 description 2
- 230000009471 action Effects 0.000 description 1
- 150000001298 alcohols Chemical class 0.000 description 1
- 229910000147 aluminium phosphate Inorganic materials 0.000 description 1
- 239000012080 ambient air Substances 0.000 description 1
- 239000003054 catalyst Substances 0.000 description 1
- 230000008859 change Effects 0.000 description 1
- 238000004891 communication Methods 0.000 description 1
- 238000003869 coulometry Methods 0.000 description 1
- 229940079593 drug Drugs 0.000 description 1
- 239000003814 drug Substances 0.000 description 1
- 230000007613 environmental effect Effects 0.000 description 1
- 238000009434 installation Methods 0.000 description 1
- 238000011835 investigation Methods 0.000 description 1
- 150000002500 ions Chemical class 0.000 description 1
- 239000000463 material Substances 0.000 description 1
- 230000001590 oxidative effect Effects 0.000 description 1
- 238000012545 processing Methods 0.000 description 1
- 230000000241 respiratory effect Effects 0.000 description 1
- XLYOFNOQVPJJNP-UHFFFAOYSA-N water Substances O XLYOFNOQVPJJNP-UHFFFAOYSA-N 0.000 description 1
Classifications
-
- G—PHYSICS
- G01—MEASURING; TESTING
- G01N—INVESTIGATING OR ANALYSING MATERIALS BY DETERMINING THEIR CHEMICAL OR PHYSICAL PROPERTIES
- G01N1/00—Sampling; Preparing specimens for investigation
- G01N1/02—Devices for withdrawing samples
- G01N1/22—Devices for withdrawing samples in the gaseous state
- G01N1/24—Suction devices
-
- A—HUMAN NECESSITIES
- A61—MEDICAL OR VETERINARY SCIENCE; HYGIENE
- A61B—DIAGNOSIS; SURGERY; IDENTIFICATION
- A61B5/00—Measuring for diagnostic purposes; Identification of persons
- A61B5/08—Detecting, measuring or recording devices for evaluating the respiratory organs
- A61B5/082—Evaluation by breath analysis, e.g. determination of the chemical composition of exhaled breath
-
- A—HUMAN NECESSITIES
- A61—MEDICAL OR VETERINARY SCIENCE; HYGIENE
- A61B—DIAGNOSIS; SURGERY; IDENTIFICATION
- A61B5/00—Measuring for diagnostic purposes; Identification of persons
- A61B5/08—Detecting, measuring or recording devices for evaluating the respiratory organs
- A61B5/097—Devices for facilitating collection of breath or for directing breath into or through measuring devices
-
- A—HUMAN NECESSITIES
- A61—MEDICAL OR VETERINARY SCIENCE; HYGIENE
- A61B—DIAGNOSIS; SURGERY; IDENTIFICATION
- A61B5/00—Measuring for diagnostic purposes; Identification of persons
- A61B5/48—Other medical applications
- A61B5/4845—Toxicology, e.g. by detection of alcohol, drug or toxic products
-
- G—PHYSICS
- G01—MEASURING; TESTING
- G01N—INVESTIGATING OR ANALYSING MATERIALS BY DETERMINING THEIR CHEMICAL OR PHYSICAL PROPERTIES
- G01N1/00—Sampling; Preparing specimens for investigation
- G01N1/02—Devices for withdrawing samples
- G01N1/22—Devices for withdrawing samples in the gaseous state
-
- G—PHYSICS
- G01—MEASURING; TESTING
- G01N—INVESTIGATING OR ANALYSING MATERIALS BY DETERMINING THEIR CHEMICAL OR PHYSICAL PROPERTIES
- G01N33/00—Investigating or analysing materials by specific methods not covered by groups G01N1/00 - G01N31/00
- G01N33/48—Biological material, e.g. blood, urine; Haemocytometers
- G01N33/483—Physical analysis of biological material
- G01N33/497—Physical analysis of biological material of gaseous biological material, e.g. breath
- G01N33/4972—Determining alcohol content
-
- G—PHYSICS
- G01—MEASURING; TESTING
- G01N—INVESTIGATING OR ANALYSING MATERIALS BY DETERMINING THEIR CHEMICAL OR PHYSICAL PROPERTIES
- G01N33/00—Investigating or analysing materials by specific methods not covered by groups G01N1/00 - G01N31/00
- G01N33/48—Biological material, e.g. blood, urine; Haemocytometers
- G01N33/50—Chemical analysis of biological material, e.g. blood, urine; Testing involving biospecific ligand binding methods; Immunological testing
- G01N33/98—Chemical analysis of biological material, e.g. blood, urine; Testing involving biospecific ligand binding methods; Immunological testing involving alcohol, e.g. ethanol in breath
-
- G—PHYSICS
- G01—MEASURING; TESTING
- G01N—INVESTIGATING OR ANALYSING MATERIALS BY DETERMINING THEIR CHEMICAL OR PHYSICAL PROPERTIES
- G01N1/00—Sampling; Preparing specimens for investigation
- G01N1/02—Devices for withdrawing samples
- G01N1/22—Devices for withdrawing samples in the gaseous state
- G01N2001/2244—Exhaled gas, e.g. alcohol detecting
Abstract
OF THE DISCLOSURE
An analyzer and a process analyze a breath sample exhaled by a subject for a
predetermined substance, particularly alcohol. An input fluid connection connects an input
unit (1) to a measuring chamber (3). A suction fluid connection connects the measuring
chamber to a suction chamber unit (5, 6), that is selectively transferrable to a with minimum
volume state or a maximum volume state. A sensor (12) measures an amount or a
concentration of the substance in the measuring chamber. A drive unit (4, 11) moves a valve
(2, 13) for the input fluid connection selectively into a closing or into a releasing end
position. The drive unit can also move the suction chamber unit between the two states. The
movement of the valve (2, 13) from one end position to the other end position is coupled with
a transfer of the suction chamber unit (5, 6) between the two states.
Description
[0001] This application claims the benefit of priority of German Patent Application
No. 10 2022 108 432.9, filed April 7, 2022, the entire contents of which are incorporated herein
by reference.
[0002] The invention relates to an analyzer (an analysis device) and a process for analyzing a
gas sample provided (input) by a subject, in particular an exhaled breath sample, for a
predetermined substance, in particular for alcohol. Such an analyzer can be used for checking
whether or not the subject has ingested alcohol, in particular ethyl alcohol (ethanol) and
optionally admixtures of other alcohols. If the subject has consumed alcohol above a
detection limit, his or her blood contains alcohol and therefore the air exhaled by the subject
contains breath alcohol. Optionally, such an analyzer can be used to determine what the
breath alcohol concentration is in his or her breath, and from this the amount of alcohol in his
blood can be deduced.
[0003] In the following, the term "alcohol" is used for a substance to be detected in the blood
of the subject, and the term "breath alcohol" is used for a substance which is then contained
in a gas sample, in particular breath sample, of the subject if his or her blood contains
alcohol.
[0004] Various portable breath alcohol analyzers have become known, for example from DE
2017 008 008 Al. A subject introduces a breath sample into a mouthpiece of the analyzer.
At least a portion of the breath sample is directed to a measuring chamber in the analyzer. An
electrochemical sensor measures at what concentration or in what amount the gas coming
from the breath sample and being in the measuring chamber contains breath alcohol. Of
course, the measurement can lead to the result that no breath alcohol above a detection limit
is contained in the gas and therefore in the breath sample.
[0005] The invention is directed to the object of providing an analyzer and a process for
analyzing a gas sample for a predetermined substance, wherein the gas sample is from a
subject to be analyzed for a predetermined substance, and wherein the analyzer and process
are intended to be more reliable than known analyzers and processes.
[0006] The object is accomplished by an analyzer having analyzer features according to the
invention and by a process having process features according to the invention. Advantageous
embodiments of the analyzer according to the invention are, as far as useful or reasonable,
also advantageous embodiments of the process according to the invention and vice versa.
[0007] The analyzer according to the invention and the process according to the invention are
capable of analyzing a gas sample for a given substance. A subject, in particular a human, has
delivered this gas sample, in particular exhaled. The substance is, in particular, breath alcohol
or another drug or other addictive substance which can be detected in a gas sample from a
subject.
[0008] The analyzer comprises an input unit. The subject can input the gas sample into this
input unit, in particular exhale, or the gas sample can be taken up by the input unit in another
way. The input unit is permanently or at least temporarily connected to the rest of the
analyzer, preferably detachably (releasably) connected.
[0009] Further, the analyzer includes a measuring chamber and an input fluid connection. A
"measuring chamber" is to be understood to mean a cavity of the analyzer, wherein the cavity
can receive a gas sample. The input fluid connection at least temporarily connects the input
unit to the measuring chamber so that, when the fluid connection is established, a fluid, in
particular a quantity of the gas sample input into the input unit, can flow from the input unit
into the measuring chamber and preferably vice versa from the measuring chamber back into
the input unit.
[0010] A sensor of the analyzer is capable of measuring an indicator of the amount and / or
concentration of the predetermined substance in a gas. At least the sensor is able to determine
whether the amount or concentration is below or above a predetermined threshold, e.g. a
detection limit. The gas that the sensor examines is located in or at the measuring chamber.
The sensor is preferably arranged in the measuring chamber or on or in at least one wall of
the measuring chamber. The sensor is capable of outputting a signal that correlates with the
amount and/or concentration of the substance.
[0011] Furthermore, the analyzer comprises a suction chamber unit, for example with a
bellows and a plate, the plate being capable of expanding and compressing the bellows and
thereby changing the volume of the space enclosed by the bellows, or with a piston-cylinder
unit. A suction fluid connection at least temporarily connects the suction chamber unit to the
measuring chamber. Through this suction fluid connection, a fluid can flow from the
measuring chamber into the suction chamber unit and back from the suction chamber unit
into the measuring chamber.
[0012] Notes:
- A fluid connection (fluid communication) is established between a first
component and a second component if a fluid, in particular a gas, can flow from the first component into the second component. It is possible that the first component is directly connected to the second component and the fluid connection is established with the aid of two overlapping openings in the two components.
- It is also possible that the fluid connection is established with the aid of a fluid
guide unit, whereby the fluid guide unit connects the two components to one another,
and a fluid can flow through the fluid guide unit. A "fluid guide unit" is understood to
be a component that is capable of guiding a fluid along a trajectory determined by the
geometry and position of the component, and ideally preventing the fluid from
leaving this trajectory. A tube and a hose are two examples of a fluid guiding unit.
- The analyzer according to the invention establishes the input fluid connection
and the suction fluid connection each at least intermittently during a use. It is possible
that neither of the two fluid connections is established in an idle state of the analyzer.
[0013] The suction chamber unit encloses a space fluid-tightly, except for a fluid connection
described below, and can be selectively transferred into a minimum volume state or into a
maximum volume state. During transfer into the minimum volume state, a fluid is conveyed
out of the suction chamber unit and forced into the suction fluid connection. This causes fluid
to be forced out of the suction fluid connection and into the measuring chamber. This event
forces (expels) fluid out of the measuring chamber and into the input fluid connection or into
a separate output fluid connection. The process of forcing fluid out of the measuring chamber
therefore causes the measuring chamber to be purged.
[0014] During the transfer into the maximum volume state, a fluid is sucked into the suction
chamber unit. This causes fluid to be sucked through the suction fluid connection into a
chamber of the suction chamber unit. As a result, fluid is drawn from the environment
through the input fluid connection into the measuring chamber. Preferably, at least a portion of this fluid originates from the input unit and contains gas delivered by the subject. Thus, the process of bringing the suction chamber unit into the maximum volume state causes at least a portion of the gas sample delivered by the subject to be drawn into the measuring chamber.
[0015] The analyzer further comprises a valve. This valve can be moved either into a closing
end position or into a releasing end position. In the closing end position, the valve closes the
input fluid connection and thereby interrupts the input fluid connection. Of course, even
when the input fluid connection is closed, unavoidable gaps or slits can occur through which
gas can pass from the input unit into the measuring chamber. In the releasing end position
and optionally also in each intermediate position, the valve at least partially releases the input
fluid connection.
[0016] Furthermore, the analyzer comprises a drive unit. Preferably, the drive unit comprises
an actuator and a rod.
[0017] On the one hand, the drive unit can selectively move the valve into the closing end
position or into the releasing end position. On the other hand, the same drive unit can
selectively transfer the suction chamber unit into the maximum volume state or into the
minimum volume state.
[0018] The drive unit is mechanically coupled to both a valve body (closure part) of the valve
and a part of the suction chamber unit. One of the following effects is achieved by these two
couplings:
- A movement of the valve into the releasing end position is synchronized with
a transfer of the suction chamber unit into the minimum volume state. Conversely, a
movement of the valve into the closing end position is synchronized with a transfer of
the suction chamber unit into the maximum volume state.
- A movement of the valve into the closing end position is synchronized with a
transfer of the suction chamber unit into the minimum volume state. Conversely, a
movement of the valve into the releasing end position is synchronized with a transfer
of the suction chamber unit into the maximum volume state.
[0019] The process according to the invention is carried out using an analyzer according to
the invention and comprises the following steps:
- Initially, the valve is in the closing end position and interrupts the input fluid
connection.
- A gas sample enters into the input unit or is taken up by the input unit.
- The drive unit moves the valve into the releasing end position so that the valve
releases the input fluid connection.
- The drive unit transfers the suction chamber unit into the maximum volume
state. This transfer sucks gas from the input unit through the input fluid connection
into the measuring chamber.
- The drive unit then transfers back the suction chamber unit to the minimum
volume state. This back transfer causes gas to be conveyed from the suction chamber
unit through the suction fluid connection into the measuring chamber. This in turn
ejects gas from the measuring chamber, which flushes (purges) the measuring
chamber.
- The drive unit moves the valve back into the closing end position.
[0020] The order in which these steps are listed is not necessarily the chronological order in
which these steps are performed. As far as reasonable, a different order is possible.
[0021] Furthermore, the process comprises the following step: The sensor measures an indicator of the concentration and/or amount of the substance, in particular of breath alcohol, in the gas that is in the measuring chamber. At least a portion of this gas in the measuring chamber, ideally all gas in the measuring chamber, originates from the input unit and therefore from the subject.
[0022] In a first alternative of the invention, the following two steps are performed
simultaneously:
- The valve is moved into the releasing end position.
- The suction chamber unit is transferred into the minimum volume state.
[0023] According to the first alternative, the following two steps are also performed
simultaneously:
- The valve is moved into the closing end position.
- The suction chamber unit is transferred into the maximum volume state.
[0024] In a second alternative of the invention, the following two steps are performed
simultaneously:
- The valve is moved into the closing end position.
- The suction chamber unit is transferred into the minimum volume state.
[0025] According to the second alternative, the following two steps are also performed
simultaneously:
- The valve is moved into the releasing end position.
- The suction chamber unit is transferred into the maximum volume state.
[0026] The characteristic that two operations are performed simultaneously includes that a
difference within a tolerance band occurs between the start times or end times of each of the
two operations.
[0027] By means of the analyzer and the process according to the invention, at least one gas
sample is sucked from the input unit into the measuring chamber. This gas sample is a part of
that quantity of gas which the subject has delivered into the input unit. As already explained,
the gas sample is sucked into the measuring chamber by transferring the suction chamber unit
into the maximum volume state. Preferably, the input unit is connected to the rest of the
analyzer at least during the period in which the gas sample is sucked into the measuring
chamber, so that it is ensured that the sucked-in gas sample originates from the gas that the
subject has exhaled or otherwise input into the input unit.
[0028] Of course, the gas sample to be analyzed can only flow from the input unit into the
measuring chamber and be analyzed there by the sensor if the valve is in the releasing end
position or at least in an intermediate position. Furthermore, in many cases, the measuring
chamber can only be flushed and made available for receiving another gas sample when the
valve is in the releasing end position or at least in an intermediate position. Only then can gas
flow out of the measuring chamber through the input fluid connection. It is also possible that
gas from the measuring chamber does not pass through the input fluid connection but leaves
the analyzer through a separate fluid connection.
[0029] With the valve in the closing end position, the measuring chamber is separated from
the input unit and preferably from the environment, ideally in a fluid-tight manner. On the
one hand, this reduces the risk of ambient conditions changing the sensor. In particular, the
risk is reduced that particles or substances from the input unit or the environment affect the
sensor or that deposits form. On the other hand, there is less risk that a component of the
sensor will evaporate, for example an electrolyte. Both ambient conditions and evaporation
can cause the sensor to deliver incorrect measurement results or even fail.
[0030] For the reasons just stated, the valve must be temporarily in the releasing position, namely to allow a sample of the gas being tested to flow into the measuring chamber, and should otherwise be in the closing position.
[0031] According to the invention, the suction chamber unit sucks a sample of the gas sample
to be examined into the measuring chamber in such a way that the suction chamber unit is
transferred into the maximum volume state. Due to this feature, in many cases a defined
amount of the gas sample to be analyzed is delivered into the measuring chamber in a
relatively short time. in many cases it would be much more difficult to determine the amount
of gas sample entering the measuring chamber if the amount depended significantly on the
strength and duration with which the subject inputs the gas sample, on the volume flow rate
at which the gas sample flows into the measuring chamber, or if the gas sample diffused into
the measuring chamber. In addition, such a procedure to move a gas sample into the
measuring chamber requires more time in many cases than the use of the suction chamber
unit according to the invention.
[0032] In many cases, the measuring chamber contains almost only the gas that has been
drawn into the measuring chamber by the suction chamber unit being transferred into the
maximum volume state. The gas that enters the measuring chamber by diffusion or by the
subject ejecting a gas sample while the suction chamber unit is at rest often is a negligible
amount. The effect of the gas in the measuring chamber being almost entirely from suction
facilitates ensuring in many cases that essentially only air from the subject's lungs enters the
measuring chamber, but little air from the upper airways or mouth. This increases the
reliability of the measurement, particularly when alcohol is to be detected in the subject's
blood. In another application, this feature makes it easier to ensure that first air from the
mouth and then air from the subject's lungs enters the measuring chamber and is analyzed
there for the substance in each case, while largely preventing air from the upper airway from entering the measuring chamber.
[0033] Thanks to the invention, only one drive unit is required both to move the valve and to
transfer the suction chamber unit. This saves one drive unit, and thus in many cases space and
electrical energy, compared to an embodiment in which two different drive units are
provided. In addition, only one drive unit needs to be controlled and monitored, rather than
two.
[0034] According to the invention, the movement of the valve from one end position into the
other end position is mechanically coupled to the transfer of the suction chamber unit from
one state into the other state, in that the same drive unit is mechanically coupled to both the
valve and the suction chamber unit. Thanks to this coupling, it is achieved in many cases that
the valve
- is only open as long as necessary, namely so that gas can flow into the
measuring chamber, and
- is closed for as long as possible, thereby separating the measuring chamber
and the sensor from the environment.
[0035] Thanks to the mechanical coupling, there is no need to use an electronic or pneumatic
control unit that couples the valve movement with the state transfer.
[0036] According to the invention, the input fluid connection connects the input unit to the
measuring chamber. In one embodiment, the input unit comprises or defines a channel
connecting the environment to the input fluid connection. Preferably, this channel tapers as
seen in a direction towards the measuring chamber. In one implementation, the input unit
further comprises a mouthpiece that can be detachably connected to a housing of the analyzer
and guides a delivered gas sample, in particular breath sample, towards the input fluid connection. These two realization forms can be combined with each other.
[0037] According to the invention, the drive unit is able to both move the valve and transfer
the suction chamber unit, thereby causing a synchronized movement of these two parts.
Preferably, the drive unit comprises an actuator that is mechanically coupled to both the valve
and the suction chamber unit.
[0038] According to the invention, the step of transferring the suction chamber unit into the
maximum volume state does the following: Gas from the input unit is sucked through the
input fluid connections into the measuring chamber. Preferably, the measuring chamber is
located between the input unit and the valve on one side and the suction chamber unit on the
other side. Particularly preferably, the input unit, the input fluid connection, the measuring
chamber, and the suction chamber unit are arranged one behind the other along a line.
Preferably, the valve is also located on this line, namely between the input unit and the
measuring chamber. The embodiment with the measuring chamber between the input unit
and the suction chamber unit leads to a particularly space-saving and robust arrangement. In
many cases, the preferred embodiment in which various components are arranged along a line
accomplishes the following: The gas sample is conveyed linearly, which reduces the risk of
unwanted turbulences.
[0039] In a preferred implementation, the drive unit additionally comprises a mechanical
valve connection element. The valve connecting element is or preferably comprises a rod or
bar. The valve comprises a closure part, which preferably functions as a valve body, and a
closure part seat, for example a sealing ring. The closure member is movable relative to the
closure member seat, preferably linearly movable in two opposite directions. When the valve
is in the closing end position, the closure member is in contact with the closure member seat,
preferably fluid-tight except for unavoidable slits and/or gaps. When the valve is in the releasing end position or in an intermediate position, a gap occurs between the closure part and the closure part seat. According to this implementation, the valve connecting element mechanically connects the actuator to the closure part. This implementation results in a particularly simple mechanical structure. The valve connecting element bridges the distance between the actuator and the closure part. This allows the actuator to be arranged at a distance from the closure part, which in some cases facilitates the positioning of the input fluid connection and the electrical supply of the actuator.
[0040] This embodiment can be combined with an embodiment in which the suction chamber
unit is located between the measuring chamber and the actuator. Preferably, the measuring
chamber is again located between the suction chamber unit and the input unit.
[0041] In another embodiment, the suction chamber unit comprises a variable volume suction
chamber having a fluid-tight wall, such as a bellows. Further, the suction chamber unit
comprises a mechanical chamber modifying element, such as a plate. It is also possible that
the suction chamber unit comprises a piston-cylinder unit, wherein the piston is movable
relative to the cylinder and the suction chamber is provided inside the cylinder and limited by
the piston. The piston then acts as the chamber modifying element. A movement of the
chamber modifying element relative to the suction chamber causes the volume of the suction
chamber to change. The suction fluid connection according to the invention connects the
suction chamber to the measuring chamber. The drive unit comprises an actuator and a
mechanical chamber connecting element. This chamber connecting element connects the
actuator to the chamber modifying element.
[0042] At least two of the just mentioned embodiments can be combined.
[0043] According to the invention, the drive unit is able to move the valve back and forth
between the releasing and the closing end positions. In one embodiment, a volume flow sensor is capable of measuring an indicator of the volume flow of gas through the input fluid connection into the measuring chamber. A "volume flow" through a fluid connection is understood to be a volume per unit time of a fluid flowing through the fluid connection. For example, the volume flow sensor measures the difference in pressure at two different measurement positions, and an evaluation unit derives the volume flow from the pressure difference. According to this embodiment, the analyzer according to the invention is configured as follows: Depending on the measured volume flow, the analyzer is able to automatically trigger the step that the drive unit moves the valve into the closing end position
(to actuate the drive unit to move the valve). This embodiment facilitates the introduction
(guiding) of a defined and/or known amount of gas into the measuring chamber and the
subsequent closing of the measuring chamber. This embodiment increases the reliability of
the measurement result. The amount of gas can be derived from the measured volume flow.
[0044] According to the invention, the input fluid connection connects the input unit to the
measuring chamber. In the releasing end position, the valve releases the input fluid
connection. In one embodiment, a fluid guide unit, for example a tube, surrounds a closure
part, e.g. a valve body, of the valve and optionally also a part of a valve connection element
of the drive unit. A gap occurs between the fluid guide unit and the valve body, such as an
annular gap. The input fluid connection passes through the fluid guide unit and includes this
interstitial space. In one embodiment, a closure part seat of the valve is adjacent to this
intermediate space.
[0045] This embodiment makes it possible in a particularly simple manner to design the
valve so that a linear movement of the closure part (the valve body, e.g.) moves the valve
from one end position to the other end position. The fluid guide unit protects to a certain
extent the closure part from mechanical damage from the outside.
[0046] According to the invention, the step of transferring the suction chamber unit into the
maximum volume state causes gas to be sucked through the input fluid connection into the
measuring chamber. In one embodiment, the step of transferring the suction chamber unit
into the minimum volume state causes gas to be conveyed, for example to be expelled,
through the input fluid connection out of the measuring chamber. This step flushes the
measuring chamber and enables it to receive a new gas sample. A separate fluid connection to
purge the measuring chamber is possible, but not required.
[0047] In a preferred embodiment, the step of moving the valve into the releasing end
position and thereby releasing the input fluid connection is triggered automatically and time
controlled or event-controlled. According to one implementation, the event is detected that
inputting the gas sample into the input unit is started. For example, the event is detected that a
mouthpiece or other input element has been placed on a base body of the analyzer or that gas
is flowing into the input element. In a first realization form, the step of moving the valve into
the releasing end position is started when a predetermined period of time has elapsed since
the event that inputting or intaking of the gas sample has been started.
[0048] In a second realization form, the step of transferring the valve into the releasing end
position is started when a predefined opening event has occurred since the start of inputting
the gas. The opening event preferably depends on the volume or amount of the gas sample
that has been input to the input unit so far and/or flows into the input unit.
[0049] Both realization forms of the preferred embodiment contribute to the fact that
essentially only air from the subject's lungs flows into the measuring chamber, but not at all
or only little air from the upper airway and the mouth. This effect increases the reliability of
correctly determining the level of alcohol in the subject's blood by analyzing the gas sample
for breath alcohol.
[0050] Gas can essentially only enter the measuring chamber when the valve is in the
releasing end position. Usually, the valve is only in an intermediate position between the two
end positions for a very short time. In one embodiment, it is ensured with higher reliability
that the amount of gas in the measuring chamber is at least approximately known. In one
embodiment, the amount of gas that has flowed into the measuring chamber so far is
measured. When the measured quantity reaches a predetermined quantity threshold, the step
of moving the valve back into the closing end position is triggered.
[0051] According to the invention, the drive unit transfers the suction chamber unit into the
state maximum volume state and into the minimum volume state. Alternative configurations
are possible as to the order in which these two steps are carried out.
[0052] In a first alternative, the suction chamber unit is in the maximum volume state before
the procedure is carried out, i.e. before a gas sample to be analyzed enters the measuring
chamber. First, the step of transferring the suction chamber unit to the minimum volume state
is performed. This flushes the measuring chamber, in particular by removing gas from a
previous gas sample from the measuring chamber. Then, the step of transferring back the
suction chamber unit to the maximum volume state is performed. As a result, a quantity of
the gas sample currently under investigation is sucked into the measuring chamber. The
sensor now measures an indicator of the amount or concentration of the substance.
[0053] In a second alternative, the reverse sequence is performed. Before the procedure is
carried out, the suction chamber unit is in the minimum volume state. First, the step of
transferring the suction chamber unit into the maximum volume state is performed. As a
result, a quantity of the gas sample currently being analyzed is drawn into the measuring
chamber. The sensor measures an indicator of the amount or concentration of the substance.
The suction chamber unit is then transferred back to the minimum volume state. This flushes the measuring chamber.
[0054] In a preferred embodiment, the analyzer comprises an input fluid guide unit. The
input fluid connection is passed (guided) through the input fluid guide unit. A portion of the
input fluid guide unit may belong to a wall of the measuring chamber. The input unit can be
connected, preferably detachably connected, to the input fluid guide unit. The input fluid
guide unit surrounds the valve, preferably completely. This implementation leads to a
particularly space-saving configuration of the analyzer and requires less installation space
than another possible arrangement of the valve. In addition, this implementation leads in
many cases to a particularly robust configuration, and the risk of the valve being damaged or
leaking due to external influences is reduced.
[0055] In a first application, a gas sample delivered by the subject is sucked once from the
input unit into the measuring chamber, where it is analyzed by the sensor. As stated above,
the invention facilitated ensuring that this gas sample consists predominantly of air from the
subject's lungs, but includes only to a small extent air from the subject's upper airway and
mouth. In this first application, the content of the substance in the blood of the subject is to be
examined.
[0056] In a second application, two gas samples delivered by the same subject are sucked,
one sample after the other, from the input unit into the measuring chamber, where the gas
samples are analyzed by the sensor. In between, the measuring chamber is rinsed out
(purged). In this second application, the analyzer is operated such that the first gas sample
consists essentially of air from the subject's mouth, and the second gas sample consists
essentially of air from the lungs. The first gas sample is used to determine whether the subject
has recently ingested alcohol or some other substance that has not yet reached the subject's
bloodstream. The second gas sample is used to examine the content of the substance in the subject's blood.
[0057] In a third application, a pre-sample is first aspirated into the measuring chamber, and
the measuring chamber is rinsed out with this pre-sample without necessarily testing the pre
sample for the substance. The pre-sample can also come from the subject or from the
environment.
[0058] In one embodiment, the analyzer is configured as a portable device and includes its
own power supply unit, preferably a set of rechargeable batteries. The analyzer may also be
configured as a stationary device and connected, or connectable, to a stationary power supply
network.
[0059] In the following, the invention is described by means of embodiment examples. The
various features of novelty which characterize the invention are pointed out with particularity
in the claims annexed to and forming a part of this disclosure. For a better understanding of
the invention, its operating advantages and specific objects attained by its uses, reference is
made to the accompanying drawings and descriptive matter in which preferred embodiments
of the invention are illustrated.
[0060] In the drawings:
[0061] Figure 1 is a schematic view showing the mode of operation of an electrochemical
sensor;
[0062] Figure 2 is a perspective view, obliquely from above, of a first embodiment of the
analyzer according to the invention;
[0063] Figure 3 is a perspective view, vertically from above, of the analyzer of Figure 2;
[0064] Figure 4 is a cross-sectional view of the analyzer of Figure 2 and Figure 3;
[0065] Figure 5 is another cross-sectional view of the analyzer of Figure 2 and Figure 3;
[0066] Figure 6 is a perspective view of a segment of the analyzer according to the first
embodiment comprising the sample inlet, the valve, the rod, the sensor, and the bellows,
wherein the measuring chamber is omitted;
[0067] Figure 7 is a cross-sectional view showing the segment of Figure 6 with the sensor
omitted;
[0068] Figure 8 is a schematic cross-sectional view of the input fluid connection to the
measuring chamber;
[0069] Figure 9 is a cross-sectional view of a second embodiment of the analyzer according
to the invention;
[0070] Figure 10a is a sectional view through the analyzer with the rod perpendicular to the
drawing planes taken along the plane A - A of Figure 3;
[0071] Figure 1Ob is a sectional view through the analyzer with the rod perpendicular to the
drawing planes taken along the plane B - B of Figure 3;
[0072] Figure 10c is a sectional view through the analyzer with the rod perpendicular to the
drawing planes taken along the plane C - C of Figure 3.
[0073] Referring to the drawings, in an embodiment example, the analyzer according to the
invention is used to analyze a breath sample exhaled by a subject, in particular a human, for a
predetermined substance, in particular breath alcohol. In the case of breath alcohol as the substance, a subject is to be analyzed to determine whether or not alcohol is present in his or her blood above a detection threshold. The subject inputs (delivers) a breath sample into a mouthpiece of the analyzer. If the subject has consumed alcohol and the alcohol in the blood has not yet completely decomposed, the breath sample delivered contains breath alcohol. A part of the delivered breath sample flows into a measuring chamber inside the analyzer. This portion is referred to below as the "measuring chamber sample". A sensor in or on the measuring chamber checks whether or not this measuring chamber sample contains breath alcohol or any other predetermined substance. The invention can also be applied to another substance that may be present in the exhaled air of a subject or in any other gas that a subject may emit.
[0074] The sensor is capable of generating a signal that correlates with the amount and/or
concentration of the given substance in the measuring chamber sample that is in the
measuring chamber. Various suitable sensors are known from the prior art, for example
electrochemical sensors, photo-optical sensors, photo-acoustic sensors, photo-ionization
sensors and heat tone sensors. Such a sensor can also be applied to the invention.
[0075] The analyzer derives the concentration of breath alcohol in the input breath sample
from the measured amount or concentration of breath alcohol in the measuring chamber
sample and the amount and / or volume of the measuring chamber sample. For example, the
amount and / or volume of the measuring chamber sample is derived depending on the
volume of the measuring chamber, which is known by the configuration of the analyzer, and/
or by measuring the volume flow into the measuring chamber multiple times and integrating
the measured values. If the substance is breath alcohol, a signal-processing evaluation unit of
the analyzer or a spatially remote evaluation unit derives the current content of alcohol in the
blood of the subject from the breath alcohol concentration in the breath sample.
[0076] As the breath sample passes through the mouthpiece, air first flows from the mouth,
then from the upper respiratory tract (upper airway), and then air from the subject's lungs
flows through the mouthpiece. To determine if the subject's blood contains alcohol, gas from
that portion of the breath sample that originates from the lungs must be tested. Ideally, only
gas originating from the subject's lungs will flow into the measuring chamber, and the
measuring chamber sample will contain only air from the lungs, but no air from the mouth
and upper airway. The following describes how this objective is achieved according to the
invention.
[0077] The analyzer of the embodiment comprises an electrochemical sensor 12. By a
"sensor" is meant a component that automatically generates a signal, preferably an electrical
signal, wherein the generated signal is an indication of the amount and/or concentration of a
predetermined substance in the measuring chamber sample. This measuring chamber sample
is located in a measuring chamber, wherein the sensor is capable of analyzing this measuring
chamber sample in the measuring chamber. An electrochemical sensor triggers a chemical
reaction, wherein the chemical reaction depends on the amount and / or concentration of the
substance to be analyzed and influences a measurable electrical detection quantity, for
example the current intensity or the electrical voltage or the electrical charge or the electrical
resistance of a component of the sensor.
[0078] Figure 1 shows schematically and by way of example the mode of operation of an
electrochemical sensor 12 as known from the prior art. The representation of Figure 1 is not
necessarily true to scale. This electrochemical sensor 12 is capable of analyzing a measuring
chamber sample Pr for breath alcohol and operates on the principle of a fuel cell with alcohol
as the fuel. Such a sensor 12 can also be used for the analyzer according to the invention. In
one embodiment, the analyzer according to the invention comprises such an electrochemical sensor 12.
[00791 The reference number 50 in Figure 1 denotes a sensor arrangement comprising an
electrochemical sensor 12 and a wall 40 for a measuring chamber 3. The wall 40 surrounds
the sensor 12 and the measuring chamber 3. In the form of implementation shown, both the
wall 40 and the sensor 12 are rotationally symmetrical about the same central axis MA. Of
course, other geometric shapes are also possible.
[0080] The measuring chamber sample Pr to be analyzed, which in the embodiment comes
from a breath sample A, flows through an opening O.e on the inlet side into the interior of the
measuring chamber 3, e.g. by being exhaled or aspirated by a subject or by diffusing into the
measuring chamber 3. In one embodiment, the measuring chamber sample Pr flows out of the
measuring chamber 3 again through an outlet side opening O.a. Thanks to this embodiment,
the sensor 12 can quickly examine several measuring chamber samples Pr in succession. It is
also possible that there is no outlet-side opening O.a and the measuring chamber sample
flows out of the measuring chamber 3 again through the inlet-side opening O.e.
[0081] The electrochemical sensor 12 comprises:
- a measuring electrode 20, which is electrically contacted by a contacting wire
34,
- a counter electrode 21, which is electrically contacted by a contacting wire 33,
- an electrolyte 28 between the two electrodes 20 and 21,
- a connecting wire 12 which electrically connects the two contacting wires 33
and 34 and in which an electrical measuring resistor 29 is arranged, and
- a current intensity sensor (amperage meter) 38 that measures the intensity I of
the current flowing through the connection wire 12.
[0082] Such an electrochemical sensor 12 is also referred to hereinafter as a membrane
electrode electrolyte (MPEE) unit.
[0083] The electrolyte 28 is or comprises an electrically conductive medium, for example
sulfuric acid or phosphoric acid or perchloric acid diluted with water. Ions can move in the
electrolyte 28. Preferably, a porous membrane provides the electrolyte 28. The electrolyte 28
provides an ionically conductive connection between the measuring electrode 20 and the
counter electrode 21, but electrically isolates the two electrodes 20 and 21 from each other.
[0084] The sensor 12 is configured such that the measuring chamber sample Pr reaches only
the measurement electrode 20, but not the counter electrode 21. In the example shown, the
measurement electrode 20 is located on a wall of the measuring chamber 3, and the wall 40
and the electrolyte 28 prevent a relevant amount of the measuring chamber sample Pr from
reaching the counter electrode 21.
[0085] The two contact wires 33 and 34 are electrically conductive and made of a material
that is not chemically attacked by the electrolyte 28, for example platinum or gold. The
electrodes 20 and 21 are also made of a chemically resistant material, for example also
platinum or gold. In many cases, the chemically resistant material of the electrodes 20, 21
additionally acts as a catalyst for a chemical reaction that depends on the substance to be
detected and is used for measurement.
[0086] In one embodiment, the electrochemical sensor 12 operates on the principle of a fuel
cell. The chemical reaction used for measurement includes the step of oxidizing the breath
alcohol in the measuring chamber sample Pr in the measuring chamber 3. Ideally, the entire
amount of breath alcohol in the measuring chamber sample Pr is oxidized.
[0087] As a result of the chemical reaction, an electric current flows between the measuring electrode 20 and the counter electrode 21 and thus through the connecting wire 12. The current intensity sensor 38 measures an indicator of the electric charge, i.e. of the total amount of electric current flowing through the connecting wire 12 (principle of coulometry).
Generally, electric current flows until all combustible gas, in this case breath alcohol, is
oxidized in the measuring chamber 3. For a given volume of measuring chamber sample Pr in
measuring chamber 3, the more breath alcohol the measuring chamber sample Pr contains
before oxidation, the higher the measured electric charge. The measured electric charge is
therefore a measure of the breath alcohol content in the measuring chamber sample Pr and
thus of the alcohol content in the blood of the subject.
[0088] Figure 2 to Figure 7 show a first embodiment of an analyzer 100 according to the
invention. Figure 9 shows a second embodiment. Figure 8 and Figure 10a, 10b and 10c are
valid for both embodiments.
[0089] Figure 2 and Figure 3 show the analyzer 100 according to the first embodiment of the
invention in a perspective view, Figure 4 and Figure 5 in two cross-sectional views.
[0090] The following additional components are mounted on a frame 9 of the analyzer 100:
- a mouthpiece 30 shown only schematically,
- a sample inlet 1,
- a connecting piece 16, which consists of a smaller part 16.1 and a larger part
16.2, the two parts 16.1, 16.2 being firmly connected to each other,
- a sensor arrangement 50 with a measuring chamber 3 and an electrochemical
sensor 12, wherein the sensor arrangement 50 can be constructed, for example, as
shown in Figure 1,
- an upstream connector 32, which is attached to a wall 40 of the measuring
chamber 3 upstream of the measuring chamber 3 and surrounds the part 16.2,
- a connection piece 10 on the outflow side, which is attached to the wall 40 of
the measuring chamber 3 downstream of the measuring chamber 3,
- a linear sliding rod 4,
- a connecting sleeve 11 through which the rod 4 is passed,
- a bellows 5 acting as the suction chamber unit of the embodiment,
- a plate 6 in the bellows 5, the plate 6 acting as the chamber modifying
element,
- an optional first measuring point MP.1 for a pressure measurement or volume
flow measurement described below,
- an optional second measuring point MP.2 for another pressure measurement or
for this volume flow measurement,
- an actuator that can move an object in two opposite directions and whose
function is described below,
- a schematically shown control unit 60, which receives a signal from the sensor
arrangement 50 and from a volume flow sensor or a pressure sensor, respectively, and
is configured to control the actuator, and
- a power supply unit not shown, for example at least one battery (accumulator),
which supplies the actuator with electrical energy.
[0091] The designations "front" and "back" and "upstream" and "downstream" refer to the
direction of flow of a gas from sample inlet I to bellows 5, i.e. from left to right in Figure 2 to
Figure 9.
[0092] The mouthpiece 30 is attachable to the sample inlet 1 and removable from the sample
inlet 1. In one embodiment, the attached mouthpiece 30 surrounds the sample inlet 1. The
mouthpiece 30 has the shape of a funnel, whereby this funnel tapers towards the sample inlet
1 when the mouthpiece 30 is attached. Thanks to this funnel shape, an overpressure is created
inside the mouthpiece 30 when a subject supplies (delivers) a breath sample A.
[0093] The mouthpiece 30 belongs to the input unit of the embodiment, the sample inlet 1
and the connecting piece 16 to the input fluid guide unit. An input fluid connection described
below passes through the input fluid guide unit and is capable of connecting the mouthpiece
to the measuring chamber 3.
[0094] The mouthpiece 30 has an opening through which the breath sample can flow to the
sample inlet 1. Preferably, further openings (not shown) are formed into the mouthpiece 30.
Breathing air can escape into the environment through these further openings, in particular if
excess pressure has developed in the mouthpiece 30. This reduces the risk that, in the event of
excess pressure in the mouthpiece 30, part of the breath sample A will return to the subject. A
mouthpiece with such openings is described by way of example in DE 10 2017 008 008 Al
(corresponding US11,474,096 (B2) is incorporated herein by reference).
[0095] The measuring chamber 3 is surrounded by the wall 40 and a cover plate 17. The
sensor 12 is arranged under the cover plate 17. In the shown embodiment example, the wall
of the sensor arrangement 50 has an outer contour in the form of a cuboid and an inner
contour in the form of a cylinder. Other geometric shapes are also possible. The sensor 12
and the measuring chamber 3 are rotationally symmetrical about the same central axis MA.
This central axis MA is perpendicular to the drawing plane of Figure 3 and lies in the
drawing planes of Figure 4 and Figure 5.
[0096] In the example shown, the actuator comprises a solenoid 7 and a reset unit in the form
of a spring which is supported on the frame 9 and connected to the solenoid 7. The power
supply unit, which is not shown, is electrically connected to the solenoid 7. Other
configurations of an actuator are also possible, for example an electric motor or a piston cylinder unit. Even a manual drive may be provided.
[0097] Also shown in the cross-sectional views of Figure 4 and Figure 5 are the following
components of the analyzer 100:
- a valve with a closure part and a closure part seat 13,
- a cavity 31 in the form of a tube in the sample inlet 1,
- a cavity 15 in the form of a tube inside the connector 16,
- the plate 6 in the bellows 5, the plate 6 being firmly connected to the rod 4,
- a guide unit 19 which guides the rod 4 linearly along the longitudinal axis of
the rod 4 and prevents lateral movement or rotation or canting of the rod 4,
- a section through the sensor 12 with the measuring electrode 20, the counter
electrode 21 and the electrolyte 28 and
- a section through the wall 40 of the measuring chamber 3.
[0098] In addition, Figure 4 and Figure 5 show how the linear sliding rod 4 and the
connecting sleeve 11 connect the sealing cone (sealing part) 2 to the solenoid 7.
[0099] In the embodiment example, the sealing part 2 has the shape of a sealing cone, and the
sealing part seat 13 has the shape of a sealing ring, which is preferably elastic. The diameter
of the sealing cone 2 is preferably larger than the diameter of the rod 4, making it possible to
make the diameter of the sealing cone 2 as large as possible and the diameter of the rod 4 as
small as possible. In any position of the rod 4, the sealing cone 2 is located in the cavity 15. A
circumferential gap Sp occurs between the sealing cone 2 and the inner wall of the cavity 15,
see Figure 5 and Figure 8.
[0100] The sealing element seat (sealing ring) 13 surrounds that end of the rod 4 which is
adjacent to the sealing cone 2 and is recessed in a recess in the wall 40. The rod 4 passes through the measuring chamber 3, cf. Figure 4 and Figure 5. In the embodiment shown, the longitudinal axis of the rod 4 is perpendicular to the central axis MA of the cylindrical measuring chamber 3 and lies in the drawing planes of Figure 3, Figure 4 and Figure 5. In one embodiment, at least one optional mixing element (not shown) in the form of a flat component is fixedly mounted on the rod 4. The mixing element or each mixing element is located inside the measuring chamber 3 in any position of the rod 4.
[0101] Figure 6 and Figure 7 show the sample inlet 1, the valve 2, 13 and the input fluid
connection between the sample inlet 1 and the measuring chamber 3 in a perspective view
and in a cross-sectional view, respectively. Figure 8 illustrates the input fluid connection
between the sample inlet 1 and the measuring chamber 3 in a schematic cross-sectional view
and in a slightly different implementation form from Figure 2 to Figure 7.
[0102] In the embodiments shown, the measuring chamber 3 is in fluid connection with the
mouthpiece 30 exclusively via the input fluid connection, and only when the valve 2, 13 is
fully or at least partially open.
[0103] Two alternative embodiments are also possible, neither of which are shown:
- In the first alternative embodiment, the mouthpiece 30 is in fluid connection
with the environment via a separate output fluid connection. Preferably, this output
fluid connection branches off from the input fluid connection upstream of the valve 2,
13. Preferably, this output fluid connection is closed when the valve 2, 13 is open and
is open when the valve 2, 13 is closed. When the output fluid connection is open,
breathing air that has been input into the mouthpiece 30 flows through the output fluid
connection into the environment, particularly when the valve 2, 13 is closed. This
embodiment reduces the risk of gas that the subject has input into the mouthpiece 30
flowing back to the subject.
- In the second alternative embodiment, the measuring chamber 3 is in fluid
connection with the environment via an outlet fluid connection. The measuring
chamber 3 can be flushed out through this outlet fluid connection. Preferably, a valve
is arranged in this outlet fluid connection, which is only opened when gas is to be
removed from the measuring chamber 3. This embodiment avoids that gas is
conducted or conveyed from the measuring chamber 3 into the mouthpiece 30 during
flushing of the measuring chamber 3.
[0104] In the illustrations from Figure 2 to Figure 7, the bellows 5 is shown in a maximum
volume state. The rod 4 couples this state in the first embodiment according to Figure 2 to
Figure 7 with a state in which the valve 2, 13 is in the closing end position.
[0105] Figure 9 shows the bellows 5 in a minimum volume state. In the second embodiment
according to Figure 9, the rod 4 couples this state with the state in which the valve 2, 13 is in
the closing end position. The same reference signs have the same meanings as in Figure 2 to
Figure 7.
[0106] Figure 9 also shows the following components:
- a connecting element 26 between the plate 6 and the solenoid 7 and
- a bolt (pin) passing through a recess in the connecting element 26 and through
a recess in a rod of the solenoid 7.
The wall structure 40 and rod 4 can be tilted or have an angular variation (sensor 12 can
rotate) relative to the solenoid 7 about the longitudinal axis of the bolt 27, thanks to the bolt
27.
[0107] Figure 10a, 10b and 10c shows three sections through the analyzer 100, with the axis
of the rod 4 perpendicular to the respective drawing plane in each section and the viewing direction of solenoids 7 directed towards the sample inlet 1. These three sections apply to both embodiments of the analyzer 100. Figure 1Oa shows a section in the plane A - A of
Figure 3, Figure 1Ob shows a section in the plane B - B of Figure 3 and Figure 1Oc shows a
section in the plane C - C of Figure 3.
[0108] The following other components of the analyzer 100 are shown in Figure 6, Figure 7,
and/or Figure 8:
- a tubular recess 18 surrounding the rod 4 and has an approximately triangular
cross-sectional area,
- a guide unit 19 for the rod 4 and
- another sealing ring 14 around the tube 16.
[0109] The cavities 31 and 15 together form a tube that continues into the recess 18. In the
embodiment example, the tube 31, 15, the gap Sp and the recess 18 together provide the input
fluid connection between the sample inlet 1 and the measuring chamber 3. The sealing cone 2
is movable back and forth between a closing end position, in which the input fluid connection
31, 15, Sp, 18 is interrupted, and a releasing end position, in which the input fluid connection
31, 15, Sp, 18 is released. In the closing end position, shown in the figures, the sealing cone 2
is in fluid-tight contact with the closing element seat (sealing ring) 13. By moving the sealing
cone 2 away from the closure element seat 13 and towards the sample inlet 1 (first
embodiment) or away from the sample inlet 1 (second embodiment), the sealing cone 2 is
moved linearly into the releasing end position.
[0110] When the sealing cone 2 is in the releasing end position or in an intermediate position
between the releasing and closing end positions, an input fluid connection 31, 15, Sp, 18 is
established between the mouthpiece 30 and the measuring chamber 3. This input fluid
connection 31, 15, Sp, 18 passes through the following components:
- the tube 31,
- the cavity 15,
- the gap Sp between the sealing cone 2 and the inner wall of the cavity 15,
- the inner space enclosed by the sealing ring 13 and
- the recess 18 around the rod 4.
[0111] When the sealing cone 2 is in the closing end position, i.e. rests against the sealing
ring 13, this input fluid connection 31, 15, Sp, 18 is interrupted.
[0112] The rod 4 and the connecting sleeve 11 connect the sealing cone 2 with the solenoid
7. The actuator with the solenoid 7 and the spring (not shown) can move the rod 4 linearly in
both directions and thus move the sealing cone 2 back and forth between the closing end
position and the releasing end position. The rod 4 is guided through the connecting sleeve 11.
[0113] The rod 4, the connecting sleeve 11 and the plate 6 are mechanically connected to
each other in such a way that they cannot move relative to each other. The connecting sleeve
11 transmits a movement of the rod 4 to the plate 6. Together with the rod 4, the linear
solenoid 7 can also move the connecting sleeve 11 and thus the plate 6 linearly.
[0114] The bellows 5 is mechanically connected to the wall 40 on the side facing the sample
inlet 1. The connecting piece 10 surrounds the bellows 5. The plate 6 limits the bellows 5 on
the opposite side. A linear movement of the plate 6 towards the sample inlet 1 compresses the
bellows 5 and transfers the bellows 5 into the minimum volume state. A linear movement of
the plate 6 in the opposite direction pulls the bellows 5 apart and transfers the bellows 5 into
the maximum volume state. The bellows 5 is in suction-fluid connection 8 with the
measuring chamber 3.
[0115] The solenoid 7, the spring, the bellows 5 and the plate 6 together form a displacement pump. Instead of a solenoid 7, the analyzer 100 can also have another controllable actuator, whereby this actuator can move the rod 4 in both directions and hold it in an end position. A manual actuator may also be provided.
[0116] Instead of a bellows 5 and a plate 6, a piston-cylinder unit (not shown) can also be
used, whereby the actuator 7 is capable of moving the piston relative to the cylinder. It is also
possible that the other actuator just mentioned is capable of moving the piston of a piston
cylinder unit. It is also possible that an electric motor is capable of moving the rod 4 linearly
in both directions.
[0117] The optional first measuring point MP.1 is in fluid connection with the sample inlet 1
or with the cavity 15 and thus in fluid connection with the input fluid connection 31, 15, Sp,
18 just described, which connects the mouthpiece 30 to the measuring chamber 3. Therefore,
the first measuring point MP.1 is in fluid connection with the mouthpiece 30 even when the
valve 2, 13 is closed. It is also possible that the first measuring point MP.1 is in fluid
connection with the recess 18. The optional second measuring point MP.2 is arranged
between the measuring chamber 3 and the solenoid 7 and is in fluid connection with the
measuring chamber 3.
[0118] Two pressure sensors, which are not shown, measure the pressure at the first
measuring point MP.1 and at the second measuring point MP.2, respectively. At each
sampling point of a sequence of sampling points, two pressure measurements are performed,
respectively. Preferably, these two pressure sensors measure the respective pressure
difference with respect to the ambient pressure in the environment of the analyzer 100.
[0119] In one embodiment, the measured values of that pressure sensor which is connected to
the first measuring point MP.1 are used to determine approximately the volume flow into the
mouthpiece 30 and thus the volume of that amount of breath sample A which has been input into the mouthpiece 30 so far. At least when the valve 2, 13 is closed, this inputted amount of breath sample A essentially causes the pressure inside the funnel-shaped mouthpiece 30 to increase. The slots in the mouthpiece 30 can only partially relieve this excess pressure. The information about the volume of the quantity delivered so far can be used to trigger the operation of opening the valve 2, 13. As already explained, only air from the subject's lungs should enter the measuring chamber 3, but not air from his or her mouth and upper airways.
How this desired effect is achieved is described in more detail below
[0120] In one embodiment, the measured values of the pressure sensor connected to the
second measuring point MP.2 are used to measure the time course of the pressure in the
measuring chamber 3. From this time course of the pressure as well as the volume of the
measuring chamber 3, which is known by the configuration of the analyzer 100, an estimated
value for the amount of the measuring chamber sample Pr can be derived.
[0121] In a further embodiment, which can be combined with the two embodiments just
described, a volume flow sensor not shown derives the difference between the measured
pressure at the first measuring point MP.1 and the measured pressure at the second measuring
point MP.2. This pressure difference is a measure of the current volume flow from and into
the measuring chamber 3. Optionally, it is also automatically checked whether the valve 2, 13
is tight, i.e. whether it actually interrupts the input fluid connection in the closing position.
[0122] Figure 8 illustrates how the rod 4 (shown dashed in Figure 9) is guided. In the
example shown, the recess 18 has a triangular cross-section so that a breath sample A can
flow past the rod 4 to the measuring chamber 3. Furthermore, the rod 4 is guided linearly by
the guide unit 19. Thanks to this guidance, the rod 4 can only move linearly in two directions
parallel to its own longitudinal axis, but cannot move laterally or tilt.
[0123] Figures 10a, 10b and 10c show the triangular cross-sectional area of cavity 18.
[0124] The following describes how the analyzer 100 collects and analyzes a breath sample
[0125] Before use, the analyzer 100 is in an idle state. No mouthpiece 30 is placed on the
sample inlet 1. A mechanical or pneumatic spring (not shown) of the actuator is supported on
the frame 9 and holds the rod 4 in a position in which the rod 4 has the maximum possible
distance from the sample inlet 1 in the first embodiment, and in a position with minimum
possible distance from the sample inlet 1 in the second embodiment. The solenoid 7 is
deactivated, i.e. no current flows through it. Thanks to the spring, the plate 6 pulls the
bellows 5 apart in the first embodiment according to Figure 2 to Figure 7, so that the bellows
has the maximum volume. In the second embodiment, the plate 6 compresses the bellows 5
in the rest state thanks to the spring, so that the bellows 5 has the minimum volume.
[0126] The sealing cone 2 is in the sealing end position prior to use, and the valve 2, 13
closes the input fluid connection 15, 18 between the sample inlet 1 and the measuring
chamber 3. Therefore, the measuring chamber 3 is not in fluid connection with the
environment. Particles, substances and other environmental influences can therefore not
affect the electrochemical sensor 12 while the analyzer 100 is at rest, and conversely there is
little risk of components of the electrolyte 28 leaving the electrochemical sensor 12 or even
the measuring chamber 3, for example due to evaporation.
[0127] In one embodiment, the mouthpiece 30 is used to input a single breath sample A and
is then discarded. In another embodiment, the mouthpiece 30 is disinfected after the input of
a breath sample A and then reused.
[0128] In either embodiment, the mouthpiece 30 is not connected to the remainder of the
analyzer 100 until a deployment of the analyzer 100 begins and a subject inputs a breath
sample A. Preferably, the event of the mouthpiece 30 being placed on the sample inlet 1 triggers the step of transferring the analyzer 100 from an idle state to a deployed state. For example, a contact switch detects the event that the mouthpiece 30 has been placed on the sample inlet 1.
[0129] During an operation, a subject inputs (delivers) a breath sample A into the attached
mouthpiece 30. This breath sample A initially contains exhaled air from the mouth and upper
respiratory tract and then exhaled air from the subject's lungs. Ideally, the analyzer 100
examines only exhaled air from the lungs. Therefore, the valve 2, 13 initially remains closed
even if the subject has already begun to input a breath sample A into the mouthpiece 30. As
mentioned above, the mouthpiece 30 preferably includes several other openings so that the
input breath sample A can fully exit into the environment as long as the valve 2, 13 is closed
and is not blown into the subject's face.
[0130] In the deployment state, the analyzer 100 automatically detects the occurrence of a
predetermined opening event.
[0131] Before the opening event has occurred, the valve 2, 13 is closed and the input air
escapes back out of the mouthpiece 30 through the slots or through the output fluid connection,
thus ensuring that air actually flows from the subject's lungs into the measuring chamber 3 and,
in particular, that no significant amount of air escapes from the mouth and upper airways.
[0132] For example, this opening event has occurred when a predetermined period of time
has elapsed since the step of putting on the mouthpiece 30. Or, the opening event has
occurred when a predetermined amount of breath sample A has been input into the
mouthpiece 30 since the step of putting on the mouthpiece 30, or when the subject has
completed the step of inputting a breath sample A. In the second alternative, a sensor
measures an indicator of the volume of gas delivered into the mouthpiece 30 or the volume
flow of gas into the mouthpiece 30, as described in more detail below.
[0133] Detection that the opening event has occurred triggers the following steps in the first
embodiment shown in Figure 2 through Figure 7:
- A circuit is closed and electric current activates the solenoid 7.
- The activated solenoid 7 pushes the rod 4 towards the sample inlet 1 against
the force of the spring.
- Moving the rod 4 towards the sample inlet 1 causes the sealing cone 2 to be
pushed away from the sealing ring (closing element seat) 13 and towards the sample
inlet 1. This causes the valve 2, 13 to open, namely to move it into the releasing end
position. This releases the input fluid connection described above between the input
unit (the mouthpiece 30 and the sample inlet 1) and the measuring chamber 3.
- Moving the rod 4 also causes the plate 6 to compress the bellows 5.
- Because the bellows 5 is compressed, gas flows from the bellows 5 through
the inlet fluid connection 8 and into the measuring chamber 3. This pushes existing
gas from the measuring chamber 3 through the inlet fluid connection 18, 15 and out of
the analyzer 100 through the sample inlet 1. As a result, the measuring chamber 3 is
purged. The purged gas in the measuring chamber 3 may be from a previous input.
- The pressure caused by compressing the bellows 5 is much greater than the
pressure caused by inputting the breath sample A into the mouthpiece 30. Therefore,
no significant amount of the input breath sample A flows into the input fluid
connection while the volume of the bellows 5 is still being reduced.
- Once the bellows 5 is fully compressed, no more gas is forced out of the
measuring chamber 3 through the input fluid connection. The valve 2, 13 is open and
gas can be sucked or flow from the mouthpiece 30 through the input fluid connection
into the measuring chamber 3.
[0134] As soon as a closing event is detected, the following steps are triggered:
- The rod 4 is again pushed away from the sample inlet 1 until the valve body 2
reaches the closure element seat 13. For example, solenoid 7 is de-energized again
and the spring moves rod 4 away from sample inlet 1.
- As soon as the valve body 2 reaches the closing element seat 13, the input
fluid connection 31, 15, Sp, 18 is closed again, and the measuring chamber 3 is
separated fluid-tightly from the mouthpiece 30 and from the environment.
- Moving the rod 4 away from the sample inlet 1 also causes the plate 6 to pull
the bellows 5 apart. Pulling the bellows 5 apart creates a negative pressure. The
negative pressure causes gas to be drawn from the mouthpiece 30 through the cavity
31 in the sample inlet 1 and the input fluid connection 31, 15, Sp, 18 in the connector
16 into the measuring chamber 3. The amount of gas drawn into the measuring
chamber 3 by this negative pressure belongs to the measuring chamber sample Pr.
- Moving the rod 4 further causes the optional mixing element or each optional
mixing element on the rod 4 to move through the measuring chamber 3, thereby
mixing the gas in the measuring chamber 3 to some degree.
- As soon as the plate 6 has completely pulled the bellows 5 apart, the bellows 5
has reached its maximum volume. The valve 2, 13 has again reached the closing end
position.
[0135] The electrochemical sensor 12 analyzes the gas sample in the measuring chamber 3,
for example as described with reference to Figure 1. Here, the measuring electrode 20
oxidizes the breath alcohol present in the measuring chamber 3. The measuring chamber
sample Pr is in the measuring chamber 3 until the rod 4 is pushed towards the sample inlet 1
again, thereby compressing the bellows 5. The time interval between
- the event that the bellows 5 is fully extended and the valve 2, 13 is closed, and
- the event that is started to compress the bellows 5 again, is available to the electrochemical sensor 12 for analysis, in particular for oxidation, of the measuring chamber sample Pr. During this period, the valve 2, 13 is closed. As a rule, this time period is sufficient to completely oxidize alcohol in the measuring chamber sample Pr.
[0136] The second embodiment according to Figure 9 has the following deviations from the
first embodiment according to Figure 2 to Figure 7:
- The sealing ring 13 is located upstream of the sealing cone 2, while in the first
embodiment the sealing ring 13 is located downstream of the sealing cone 2.
- At rest, the spring, which is not shown, holds the rod 4 in a position in which
the rod 4 is the smallest possible distance from the sample inlet 30.
- The activated solenoid 7 pulls the rod 4 away from the sample inlet 1 against
the force of the spring.
- Moving the rod 4 away from the sample inlet 1 causes the sealing cone 2 to
move away from the sealing ring 13 and toward the measuring chamber 3, thereby
opening the valve 2, 13.
- In addition, moving the rod 4 away from the sample inlet 1 causes the plate 6
to pull the bellows 5 apart.
- Because the bellows 5 is pulled apart, gas flows through the input fluid
connection 31, 15, Sp, 18 into the measuring chamber 3. The gas that flows into the
measuring chamber 3 in this manner belongs to the measuring chamber sample Pr.
- The closing event triggers the step of pushing the rod 4 back towards the
sample inlet 1, for example by the spring.
- The sealing cone 2 is moved away from the measuring chamber 3 and towards
the sealing ring 13. As soon as the sealing cone 2 has reached the sealing ring 13, the
valve 2, 13 is closed again.
- Moving the rod 4 toward the sample inlet 1 also causes the plate 6 to push the bellows 5 back together. The pushing together of the bellows 5 causes an overpressure. This overpressure causes gas, and thus the measuring chamber sample
Pr, to be pushed out of the bellows 5 through the suction fluid connection 8 and into
the measuring chamber 3. This causes gas to be pushed out of the measuring chamber
3 through the input fluid connection 15, Sp, 18 and through the cavity 31 into the
sample inlet 1. This flushes the measuring chamber 3.
[0137] In the second embodiment according to Figure 9, the following time period is
available for the sensor 12 to analyze the measuring chamber sample Pr: the time period
between
- the event that the bellows 5 is fully extended, and
- the event that the collapsing of the bellows 5 is started again.
During this period, the valve 2, 13 is fully open.
[0138] In order for the electrochemical sensor 12 to reliably analyze a gas and thus also the
measuring chamber sample Pr in the measuring chamber 3 for the presence of breath alcohol
and to measure the amount or concentration of breath alcohol in the measuring chamber 3, it
should be known at least approximately what amount (mass) of the breath sample A is in the
measuring chamber 3 during the analysis, thus what amount the measuring chamber sample
Pr has. Based on the design of the analyzer 100, the volume of the measuring chamber 3 is
known. The difference between the maximum volume and the minimum volume of the
bellows 5 is also known by design. Ideally, only air from the subject's lungs flows into the
measuring chamber 3, but no air from the mouth and upper airways, so that the measuring
chamber sample Pr consists only of air from the lungs.
[0139] In both of the above-described embodiments, gas is drawn into the measuring
chamber 3 by pulling the bellows 5 apart, thereby changing it from the minimum volume state to the maximum volume state. The difference between the maximum volume and the minimum volume of the bellows 5 is in many cases equal to the volume of breathing air drawn into the measuring chamber 3 from the mouthpiece 30.
[0140] In addition, during a period of time when the valve 2, 13 is or will be open and at the
same time the bellows 5 is not moved, gas may flow into the measuring chamber 3, for
example because the subject continues to exhale further or by diffusion. In many cases,
however, the amount of gas that flows into the measuring chamber 3 when the bellows 5 is
not moving can be neglected.
[0141] In one embodiment, a pressure sensor that is in fluid connection with the measuring
position MP.1 measures the time course of an indicator of the overpressure in the mouthpiece
relative to the ambient pressure. From this time course of pressure, it is possible in some
cases to derive which volume of breathing gas flows into the measuring chamber 3 in a
period of time in which the valve 2, 13 is or becomes open and at the same time the bellows 5
is not moved.
[0142] In one embodiment, a volume flow sensor measures the difference between the
pressures at the two measuring points MP.1 and MP.2 and determines the volume flow from
this. By integrating over a certain period of time, the volume flowing through the input fluid
connection 31, 15, Sp, 18 into the measuring chamber 3 during this period of time is derived
from the volume flow. This time span is, for example, equal to the time span in which the
valve 2, 13 is open and at the same time the bellows 5 is not moved. Optionally, the
measuring time period additionally comprises the time period in which the valve body 2 is
moved. It is also possible that this measurement time period also includes the time period in
which the bellows 5 is pulled apart, so that the volume flow sensor is also used to measure
which volume is sucked into the measuring chamber 3.
[0143] To deliver a valid breath sample A, the subject must exhale into the mouthpiece 30
during the procedure just described and thereby deliver the breath sample A at least until the
bellows 5 is fully extended. If the subject cancels the delivery of the breath sample A before
then, a corresponding message is preferably output in a form that can be perceived by a
human. Preferably, the patient can then deliver another breath sample A.
[0144] Various embodiments of how the opening event may be determined are described
below. As mentioned earlier, the valve 2, 13 is then started to move to the releasing end
position when the opening event is detected. Ideally, the opening event has occurred when air
from the subject's lungs has reached the mouthpiece 30.
- In one embodiment, the opening event has occurred when a predetermined
period of time has elapsed since the mouthpiece 30 was placed on the mouthpiece.
- In another embodiment, an approximate measurement is made of the amount
of exhaled air the subject has input into the mouthpiece 30 since the mouthpiece 30
was put in place. As explained above, in one embodiment, a pressure sensor in fluid
connection with the first measurement point MP.1 measures an indicator of the
positive pressure in the mouthpiece 30 relative to the ambient pressure several times
in succession. An estimated value for the previously input volume is derived at least
once from the measured values for the pressure difference. When the volume
delivered so far reaches a predetermined volume threshold, the opening event has
occurred. This volume threshold is preferably equal to the average volume of the
mouth and upper airway of an adult.
- Another embodiment can be used, in particular, in conjunction with the output
fluid connection described above and not shown, namely when the output fluid
connection connects the mouthpiece 30 to the environment. As long as the valve 2, 13
is closed, the respiratory air that the subject has input into the mouthpiece 30 is passed through the output fluid connection to the environment. The volume flow sensor described above with the two measuring positions MP.1 and MP.2 measures the volume flow through the input fluid connection 31, 15, Sp, 18 and the output fluid connection. The volume delivered so far is derived from the measured volume flow.
As soon as the volume delivered so far reaches the volume threshold, the opening
event has occurred.
[0145] The step of starting the movement of the valve 2, 13 back into the closing end
position is triggered by the closing event. Various configurations are possible as to when the
closing event has occurred:
- In one embodiment, the closing event occurs as soon as the valve 2, 13 has
reached the releasing end position. The valve 2, 13 thus remains in the releasing end
position for only a very short period of time, ideally for only one instant. Gas is drawn
into the measuring chamber 3 exclusively by the bellows 5 being pulled apart, i.e.
being transferred from the with minimum volume state into the maximum volume
state. The quantity, for example the mass, of the measuring chamber sample Pr that
enters the measuring chamber 3 is determined by the difference between the
maximum volume and the minimum volume of the bellows 5.
- In another embodiment, it is automatically determined when the chemical
reaction in the measuring chamber 3 has ended. At the end of the chemical reaction,
all breath alcohol in the measuring chamber 3 is oxidized. To determine this event, the
time course of the signal generated by the sensor 12 is determined. If the signal from
the sensor 12 remains approximately constant, the chemical process is complete. The
completion of the chemical process acts as the closing event.
This other embodiment can be used in particular in conjunction with the second
embodiment (Figure 9). This is because in the second embodiment, the closing event causes the bellows 5 to be compressed and the measuring chamber sample Pr to be forced out of the measuring chamber 3, thereby flushing the measuring chamber 3.
Thus, by this time, the analysis of the measuring chamber sample Pr must be
completed. Before this, the input fluid connection is established.
[0146] In the embodiments described so far, breathing air, which ideally comes only from the
subject's lungs, enters the measuring chamber 3 and functions there as the measuring
chamber sample Pr to be analyzed. It is possible that a preliminary sample is additionally
drawn into the measuring chamber 3 in advance and expelled from the measuring chamber 3
again before air from the subject's lungs enters the measuring chamber 3. The bellows 5 is
thus pulled apart and compressed again twice in order to test the same subject for alcohol. As
a rule, this presample consists predominantly of air originating from the mouth and/or the
upper respiratory tract of the subject. The measuring chamber 3 is rinsed out with the aid of
the preliminary sample. In one embodiment, the level of breath alcohol in the mouth and/or in
the upper respiratory tract of the subject is also determined at least approximately. In another
embodiment, the presample is used to bring the electrodes 20, 21 of the sensor 12 to the
temperature of the breath sample A. Typically, the breath sample A has a higher temperature
than the ambient air. This embodiment increases the reliability of the measurement result in
some cases. The two embodiments just described can be combined.
[0147] The bellows 5 is in fluid connection with the measuring chamber 3 through the inlet
fluid connection 8. The action of compressing the bellows 5 causes gas to be forced into the
measuring chamber 3 through the inlet fluid connection 8, thereby purging the measuring
chamber 3. In the embodiments described thus far and shown in the figures, the gas that is
forced out of the measuring chamber 3 is forced into the mouthpiece 30 through the input
fluid connection 31, 15, Sp, 18.
[0148] In a different and not shown embodiment, the analyzer additionally comprises an
outlet fluid connection. The measuring chamber 3 is in fluid connection with the environment
via this outlet fluid connection. A three-way valve can optionally be brought into one of the
following three positions:
- to an inlet position where the three-way valve clears the inlet fluid connection
31, 31, 15, Sp, 18 while blocking the outlet fluid connection,
- to an outlet position in which the three-way valve releases the outlet fluid
connection while blocking the input fluid connection 31, 31, 15, Sp, 18, and
- optionally to a blocking position in which the three-way valve blocks both
fluid connections.
[0149] During the process of pulling the bellows 5 apart, the three-way valve is in the inlet
position so that gas can flow through the inlet fluid connection 31, 15, Sp, 18 into the
measuring chamber 3. During the process of compressing the bellows 5, the three-way valve
is in the outlet position so that gas can flow out of the measuring chamber 3 through the
outlet fluid connection. This embodiment results in gas being expelled into the environment
rather than into the mouthpiece 3 when the measuring chamber 3 is purged. Preferably, the
three-way valve is in the closed position while the bellows 5 is not moved.
[0150] In one embodiment, the opening event causes the three-way valve to move to the inlet
position. In a preferred embodiment, the closing event causes the three-way valve to move to
the outlet position.
[0151] While specific embodiments of the invention have been shown and described in detail
to illustrate the application of the principles of the invention, it will be understood that the
invention may be embodied otherwise without departing from such principles.
List of reference signs
1 Sample inlet, surrounds tube 31, belongs to input fluid guide unit
2 Linearly movable sealing cone, acting as a valve body and as a closure part,
movable relative to the valve body seat 13, arranged upstream (first
embodiment) or downstream (second embodiment) of the valve body seat
13
3 Measuring chamber, receives a sample flowing in through the sample inlet
1, surrounds the sensor 12, is surrounded by the wall 40
4 Rod, connects the sealing cone 2 with the solenoid 7, guided through the
connecting sleeve 11 and guided through the measuring chamber 3, belongs
to the mechanical connecting element
Bellows capable of generating a negative pressure and a positive pressure
in the measuring chamber 3, is pulled apart and compressed by the plate 6,
acts as a suction chamber
6 Plate, is able to pull apart and compress the bellows 5, acts as a chamber
modifying element
7 Solenoid, linearly moves rod 4 parallel to its longitudinal axis, longitudinal
axis, acts as actuator
8 Suction fluid connection between the measuring chamber 3 and the bellows
5
9 Frame (rack) on which the sample inlet 1, the wall 40, the sensor 12 and the
solenoid 7 are mounted
Outflow-side connection piece, attached to measuring chamber 3
11 Connecting sleeve, through which the rod 4 is passed, firmly connected to
the rod 4 and to the plate 6, belongs to the mechanical connecting element
12 Electrochemical sensor in the measuring chamber 3, comprises electrodes
20 and 21 and electrical contacts 33, 34, is capable of determining a
measure of the concentration of breath alcohol in the measuring chamber
sample Pr
13 Sealing ring around the rod 4, acts as a valve body seat and thus as a
closure part seat for the sealing cone (valve body) 2, arranged downstream
(first embodiment) or upstream (second embodiment) from the sealing cone
2
14 Further sealing ring, arranged around the tube 16
Cavity in connecting piece 16
16 Connecting piece between the sample inlet 1 and the sealing cone 2,
surrounds the cavity 15, comprises the parts 16.1 and 16.2, belongs to the
input fluid guide unit
16.1 Smaller part of the connector 16
16.2 Larger part of the connector 16
17 Cover plate for the sensor 12
18 Recess belonging to an input fluid connection between the cavity 15 and
the measuring chamber 3
19 Guide unit that guides the rod 4 linearly
Measuring electrode of the sensor 12, is contacted by the electrical contact
34
21 Counter electrode of the sensor 12, is contacted by the electrical contact 33
22 Electrical connection between contacts 33 and 34
Stop element on the sample inlet 1, limits a movement of the mouthpiece
30 towards the measuring chamber 3.
26 Connecting element between the plate 6 and the solenoid 7
27 Bolt, passing through a recess in the connecting element 26 and in a rod 4
of the solenoid element 7
28 Electrolyte between the two electrodes 20 and 21
29 Electrical measuring resistance between the two electrodes 20, 21
Funnel-shaped mouthpiece, directs a breath sample A into the sample inlet
1
31 Tube inside the sample inlet 1
32 Inlet-side connection piece, attached to the measuring chamber 3,
surrounds the larger part 16.2
33 Electrical contacting of the counter electrode 21
34 Electrical contacting of the measuring electrode 20
38 Current sensor, measures the strength of the current flowing through the
electrical connection 22
Wall of measuring chamber 3
Sensor arrangement, comprises a sensor 12 and a measuring chamber 3
Control unit
100 Analyzer, includes mouthpiece 30, frame 9, sample inlet 1, measuring
chamber 3, sensor 12, rod 4, valve 2, 13, actuator with solenoid 7 and
connecting sleeve 11
A Breath sample to be analyzed for breath alcohol contains the measuring
chamber sample Pr, which is aspirated into the measuring chamber 3
MA Coinciding center axis of the measuring chamber 3 and the sensor 12
MP.1 First measuring point, is in fluid connection with the cavity 15 or recess 18
and thereby in fluid connection with the mouthpiece 30
MP.2 Second measuring point, is in fluid connection with the measuring chamber
3
O.a Outlet-side opening in the housing 11, through which the measuring
chamber sample Pr flows out of the measuring chamber 3
0.e Opening on the inlet side in the housing 11, through which the measuring
chamber sample Pr flows into the measuring chamber 3
Pr Measuring chamber sample, which is that part of the breath sample A
emitted by the subject that enters the measuring chamber 3
Sp Circumferential gap between the sealing cone 2 and the inner wall of the
cavity 15
Claims (16)
1. An analyzer for analyzing a gas sample delivered by a subject for a predetermined
substance, the analyzer comprises:
an input unit configured to input or receive the gas sample;
a measuring chamber, the analyzer being configured to at least temporarily provide an
input fluid connection between the input unit and the measuring chamber;
a sensor configured to measure an indicator of an amount of the substance in a gas
located in the measuring chamber and/or a concentration of the substance in a gas located in
the measuring chamber;
a suction chamber unit configured to be selectively transferred into a minimum
volume state or a maximum volume state, the analyzer being configured to at least
temporarily provide a suction fluid connection between the suction chamber unit and the
measuring chamber;
a valve configured to be moved into a closing end position in which the valve
interrupts the input fluid connection and to be moved into a releasing end position in which
the valve releases the input fluid connection; and
a drive unit configured to selectively move the valve into the closing end position or
into the releasing end position and to selectively transfer the suction chamber unit into the
minimum volume state or into the maximum volume state, the drive unit being mechanically
coupled to the valve and being mechanically coupled to the suction chamber unit such that:
a movement of the valve into the releasing end position is synchronized with a
transfer of the suction chamber unit into the minimum volume state, and a movement
of the valve into the closing end position is synchronized with a transfer of the suction
chamber unit into the maximum volume state; or a movement of the valve into the releasing end position is synchronized with a transfer of the suction chamber unit into the maximum volume state, and a movement of the valve into the closing end position is synchronized with a transfer of the suction chamber unit into the minimum volume state, wherein the analyzer is configured such that a transfer of the suction chamber unit into the maximum volume state causes gas to be sucked out of the input unit through the input fluid connection into the measuring chamber.
2. An analyzer according to claim 1, wherein:
the drive unit comprises: an actuator; and a mechanical valve connecting element;
the valve comprises a closure part; and a closure part seat; and
the valve connecting element mechanically connects the actuator to the closure part.
3. An analyzer according to claim 1 or claim 2, wherein the measuring chamber is
located between the input unit and the suction chamber unit.
4. An analyzer according to any one or more of claims 1 through 3, wherein:
the drive unit comprises an actuator mechanically coupled to the valve and
mechanically coupled to the suction chamber unit; and
the suction chamber unit is located between the measuring chamber and the actuator.
5. An analyzer according to any one or more of claims 1 through 4, wherein:
the suction chamber unit comprises a suction chamber with variable volume and a
chamber modifying element; the drive unit comprises an actuator and a mechanical suction chamber connecting element; the suction fluid connection connects the suction chamber to the measuring chamber; a movement of the chamber modifying element relative to the suction chamber causes the volume of the suction chamber to be changed; and the suction chamber connecting element mechanically connects the actuator to the chamber modifying element.
6. An analyzer according to claim 5, wherein
the drive unit comprises: an actuator; and a mechanical valve connecting element;
the valve comprises a closure part; and a closure part seat;
the valve connecting element mechanically connects the actuator to the closure part
and comprises the suction chamber connecting element.
7. An analyzer according to any one or more of claims 1 through 6, further
comprising a volume flow sensor configured to measure an indicator of a volume flow of a
gas through the input fluid connection into the measuring chamber, wherein the analyzer is
configured to actuate the drive unit to move the valve into the closing end position depending
on the measured volume flow.
8. An analyzer according to any one or more of claims 1 through 7, further
comprising a fluid guide unit, wherein:
the valve comprises a closure part;
the fluid guide unit surrounds the closure part;
an intermediate space is present between the fluid guide unit and the closure part; and the input fluid connection passes through the fluid guide unit and includes the intermediate space.
9. An analyzer according to any one or more of claims 1 through 8, wherein the
analyzer is configured such that the transfer of the suction chamber unit into the minimum
volume state causes gas to be conveyed out of the measuring chamber through the input fluid
connection.
10. An analyzer according to any one or more of claims 1 through 9, further
comprising an input fluid guide unit, wherein:
the input unit is configured to be connected to the input fluid guide unit;
the input fluid connection passes through the input fluid guide unit; and
the input fluid guide unit at least partially surrounds the valve.
11. A process for analyzing a gas sample delivered by a subject for a predetermined
substance, the process comprising the steps of:
providing an analyzer, wherein the analyzer comprises an input unit; a measuring
chamber; a sensor; a suction chamber unit which can be selectively transferred into a
minimum volume state and a maximum volume state; a valve and a drive unit, wherein the
analyzer at least temporarily provides an input fluid connection between the input unit and
the measuring chamber and at least temporarily provides a suction fluid connection between
the suction chamber unit and the measuring chamber;
establishing the valve in a closing end position in which the valve interrupts the input
fluid connection;
inputting the gas sample into the input unit; with the drive unit, moving the valve into a releasing end position in which the valve releases the input fluid connection; with the drive unit, transferring the suction chamber unit into the maximum volume state so that gas is sucked out of the input unit through the input fluid connection into the measuring chamber; subsequent to the step of transferring the suction chamber unit into the maximum volume state, with the drive unit, transferring the suction chamber unit into the minimum volume state so that gas is conveyed from the suction chamber unit through the suction fluid connection into the measuring chamber and gas is thereby expelled from the measuring chamber; with the drive unit, moving the valve back into the closing end position; and with the sensor, measuring an indicator of a concentration of the substance in the gas located in the measuring chamber and/or an indicator of an amount of the substance in the gas located in the measuring chamber, wherein either: the step of moving the valve into the releasing end position and the step of transferring the suction chamber unit into the minimum volume state are performed simultaneously, and the step of moving back the valve into the closing end position and the step of transferring the suction chamber unit into the maximum volume state are performed simultaneously, or the step of moving the valve into the closing end position and the step of transferring the suction chamber unit into the minimum volume state are performed simultaneously, and the step of moving back the valve to the releasing end position and the step of transferring the suction chamber unit to the maximum volume state are performed simultaneously.
12. A process according to claim 11, wherein:
an event is detected that the input of the breath sample into the input unit is started,
and the step of moving the valve into the releasing end position is started;
the event comprises a predefined period of time has elapsed since the breath sample
entered the input unit and / or an opening event has occurred after the start of breath sample
delivery, wherein the opening event depends on a measure of the volume or amount of the
breath sample previously input into the input unit.
13. A process according to any one or more of claims 11 through 12, wherein at least
once, a measure of the amount of gas that has so far flowed into the measuring chamber after
the start of the step of moving the valve into the releasing end position is measured, and upon
the measured quantity having reached a predetermined quantity limit, the step of moving the
valve back into the closing end position is triggered.
14. A process according to any one or more of claims 11 through 13, wherein before
carrying out the process, the suction chamber unit is in the maximum volume state, and the
step of changing the suction chamber unit to the minimum volume state is carried out before
the step of changing the suction chamber unit to the maximum volume state.
15. A process according to any one or more of claims 11 through 14, wherein before
carrying out the process, the suction chamber unit is in the minimum volume state, and the
step of changing the suction chamber unit into the maximum volume state, is carried out
before the step of changing the suction chamber unit into the minimum volume state.
16. A process according to any one or more of claims 11 through 15, wherein by
means of a mechanical coupling of the drive unit with the valve and with the suction chamber
unit, the drive unit moves the valve into the one end position and the drive unit transfers the
suction chamber unit to the minimum or maximum volume state.
40 MA 3 Ö.e Ö.a Pr
50
29 34 20 1/12
28 12 I
38 21 22 33 FIG. 1 (State of the Art) 40
Applications Claiming Priority (2)
| Application Number | Priority Date | Filing Date | Title |
|---|---|---|---|
| DE102022108432.9 | 2022-04-07 | ||
| DE102022108432.9A DE102022108432A1 (en) | 2022-04-07 | 2022-04-07 | Analysis device with a positive displacement pump and a valve and analysis method with such an analysis device |
Publications (2)
| Publication Number | Publication Date |
|---|---|
| AU2023201986A1 AU2023201986A1 (en) | 2023-10-26 |
| AU2023201986B2 true AU2023201986B2 (en) | 2024-01-25 |
Family
ID=85781979
Family Applications (1)
| Application Number | Title | Priority Date | Filing Date |
|---|---|---|---|
| AU2023201986A Active AU2023201986B2 (en) | 2022-04-07 | 2023-03-31 | Analyzer with a positive displacement pump and a valve and analysis process with such an analyzer |
Country Status (6)
| Country | Link |
|---|---|
| US (1) | US20230324263A1 (en) |
| EP (1) | EP4257039A1 (en) |
| JP (1) | JP2023155207A (en) |
| AU (1) | AU2023201986B2 (en) |
| CA (1) | CA3194629A1 (en) |
| DE (1) | DE102022108432A1 (en) |
Family Cites Families (4)
| Publication number | Priority date | Publication date | Assignee | Title |
|---|---|---|---|---|
| US3622278A (en) | 1969-04-21 | 1971-11-23 | Hittman Associates Inc | Method and means for breath analysis |
| DE202004020736U1 (en) | 2003-05-23 | 2006-01-12 | Sensatronic Gmbh | Quantitative sampling pump transferring gases, e.g. exhaled breath for alcohol analysis, comprises electrically-driven piston-cylinder unit |
| US8505360B2 (en) | 2010-08-09 | 2013-08-13 | Interceptor Ignition Interlocks Inc. | Breath sampling methodology having improved reliability |
| DE102017008008A1 (en) | 2017-08-25 | 2019-02-28 | Dräger Safety AG & Co. KGaA | Breath alcohol measurement with non-contact sample dispensing |
-
2022
- 2022-04-07 DE DE102022108432.9A patent/DE102022108432A1/en active Pending
-
2023
- 2023-03-29 EP EP23164882.5A patent/EP4257039A1/en active Pending
- 2023-03-30 CA CA3194629A patent/CA3194629A1/en active Pending
- 2023-03-31 AU AU2023201986A patent/AU2023201986B2/en active Active
- 2023-04-03 US US18/194,683 patent/US20230324263A1/en active Pending
- 2023-04-06 JP JP2023061991A patent/JP2023155207A/en active Pending
Also Published As
| Publication number | Publication date |
|---|---|
| AU2023201986A1 (en) | 2023-10-26 |
| US20230324263A1 (en) | 2023-10-12 |
| DE102022108432A1 (en) | 2023-10-12 |
| JP2023155207A (en) | 2023-10-20 |
| CA3194629A1 (en) | 2023-10-07 |
| EP4257039A1 (en) | 2023-10-11 |
Similar Documents
| Publication | Publication Date | Title |
|---|---|---|
| US3661528A (en) | Breath sampler | |
| US4297871A (en) | Gas sampling devices | |
| US20150065901A1 (en) | Universal breath sampling and analysis device | |
| US7329390B2 (en) | Device and process for measuring breath alcohol | |
| US5739412A (en) | Gas sampling system having a mouthpiece | |
| JPH07284488A (en) | Exhalation automatically sampling method and apparatus | |
| KR20130129405A (en) | Method for measuring breath alcohol concentration and apparatus therefor | |
| AU2023201986B2 (en) | Analyzer with a positive displacement pump and a valve and analysis process with such an analyzer | |
| KR101371678B1 (en) | Drunkometer | |
| CN218391088U (en) | Gas detection system of many respiratory tracts | |
| CN111526790A (en) | Portable fluid sampling device, system for using the same, and methods of making and using the same | |
| EP3326523A1 (en) | Fat burning analyser | |
| EP0302681A2 (en) | Fluid sampling systems | |
| JPH08313408A (en) | Breath sampling and analyzing apparatus | |
| KR102030278B1 (en) | Breath alcohol analyzer for low range concentration | |
| CN114403853A (en) | Portable dispersion residual qi lung function tester | |
| US20230400476A1 (en) | Analyzing apparatus with a motor and a cam disk and analyzing process using such analyzing apparatus | |
| EP1109018B1 (en) | Syringe apparatus for calibrating carbon monoxide lung diffusion capacity analyser | |
| CN111677913A (en) | Rotary valve for gas sampling | |
| JP7150324B2 (en) | Disposable inspection device and analyzer using said inspection device | |
| CN111358466A (en) | Exhaled gas detection equipment and detection method | |
| EP4140405A1 (en) | Loop-type sampling device and breathalyzer comprising same | |
| JPH08313407A (en) | Breath sampling and analyzing apparatus | |
| JP2017161263A (en) | Terminal expiration measuring apparatus and terminal expiration measuring method | |
| KR20230026791A (en) | Automatic sample collection device, fully automated device for testing virus infection using the same and real time automatic diagnostic system |